Update intermediate intro lecture

intermediate/lectures/Welcome - Introduction/README.md

@@ -1,20 +1,59 @@
 == Welcome
 
-Hi. Welcome to Intermediate Sensu. For this course, I'm going to assume you know the basics, and we are going to be focusing on "Running in Production". What does that mean? It means we'll talk about:
+Hi, welcome and thank you for enrolling in my course on Intermediate Sensu.
+
+For this course, I'm going to assume you know the basics. If you haven't
+taken my previous Introduction to Sensu course, please take it first.
+The Introductory course will lay the groundwork for the ideas and
+methods I'll be using in this course. It really is important to have a
+solid mental model of how sensu works, so please take it first.
+
+== Course Outline
+
+What should you expect from this course?
 
 === Configuration Management
 
-Config management is near and dear to my heart. It is the key to getting reproducable configuration for any system, and Sensu is no different. I'll cover all the popular configuration management systems.
+First, configuration management.
+
+Config management is near and dear to my heart. It is the key to getting
+reproducible configuration for any system, and Sensu is no different. I'll
+cover all the popular configuration management systems.
+
+In my opinion, if you can't rebuild your infrastructure from a git repo
+and a tool, you are doing it wrong. I'll show you how to build Sensu clusters
+from scratch using configuration management.
 
 === Utilizing third-party Check plugins and Handlers
 
-External check plugins and handlers provide a lot of value to Sensu, but they don't come installed out of the box. I'll show you how to take advantage of these, and even write your own.
+External check plugins and handlers provide a lot of value to Sensu, but they
+don't come installed out of the box.
+
+In the intro class I showed how to install check plugins and handlers from
+Github. I'll cover this in more depth and actually show you how to make your
+own.
+
+Eventually with any monitoring system you will find yourself needing to make
+your own custom check script, and maybe even your own Sensu handler. I'll
+show you how to make both, from scratch.
 
 === More advanced event routing
 
-If you are going to run Sensu in production, it means you need real actionable alerts. For example sending your important alerts to Pagerduty and sending other things to email, or setting up aggregation checks across a fleet of webservers. I'll cover this sort of event routing.
+If you are going to run Sensu in production, it means you need real actionable
+alerts. For example sending your important alerts to Pagerduty and sending
+other things to email, or setting up aggregation checks across a fleet of
+webservers. I'll cover this sort of event routing. And I'll talk about how
+to tune Sensu to prevent alert floods and not spam your team.
 
 === Security
 
-Having a production Sensu environment implies that it is secure. So I'll cover adding SSL to the transport and point out other places to harden Sensu or other common security gotchas you might encounter building out your Sensu infrastructure.
+Having a production Sensu environment implies that it is secure. So I'll cover
+adding SSL to the transport and point out other places to harden Sensu or other
+common security gotchas you might encounter building out your Sensu
+infrastructure.
+
+== Conclusion
 
+There are lots of things covered in this course. You can think of it as
+"accelerated experience", where you get to see what it takes to run Sensu
+in a real life environment, but in course form :)